diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 714201fa9e6f1478a08525c8d0c5468009cdd66d..5c8de74f5b406de1758f30c4334103e73824ea59 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1298,6 +1298,8 @@ extern void ext4_set_bits(void *bm, int cur, int len);
/* Metadata checksum algorithm codes */
#define EXT4_CRC32C_CHKSUM 1
+#define EXT4_LABEL_MAX 16
+
/*
* Structure of the super block
*/
@@ -1347,7 +1349,7 @@ struct ext4_super_block {
/*60*/ __le32 s_feature_incompat; /* incompatible feature set */
__le32 s_feature_ro_compat; /* readonly-compatible feature set */
/*68*/ __u8 s_uuid[16]; /* 128-bit uuid for volume */
-/*78*/ char s_volume_name[16]; /* volume name */
+/*78*/ char s_volume_name[EXT4_LABEL_MAX]; /* volume name */
/*88*/ char s_last_mounted[64] __nonstring; /* directory where last mounted */
/*C8*/ __le32 s_algorithm_usage_bitmap; /* For compression */
/*
@@ -3094,6 +3096,9 @@ extern int ext4_group_extend(struct super_block *sb,
struct ext4_super_block *es,
ext4_fsblk_t n_blocks_count);
extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
+extern unsigned int ext4_list_backups(struct super_block *sb,
+ unsigned int *three, unsigned int *five,
+ unsigned int *seven);
/* super.c */
extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
@@ -3108,6 +3113,8 @@ extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait);
extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
extern int ext4_calculate_overhead(struct super_block *sb);
+extern __le32 ext4_superblock_csum(struct super_block *sb,
+ struct ext4_super_block *es);
extern void ext4_superblock_csum_set(struct super_block *sb);
extern int ext4_alloc_flex_bg_array(struct super_block *sb,
ext4_group_t ngroup);
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 798d9d82879560d3c50cd7e7a9a65ee2fd7f6017..bbbedf27b71c4adcf5d098d9b61476fb8edc11c4 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -27,6 +27,248 @@
#include "fsmap.h"
#include <trace/events/ext4.h>
+typedef void ext4_update_sb_callback(struct ext4_super_block *es,
+ const void *arg);
+
+/*
+ * Superblock modification callback function for changing file system
+ * label
+ */
+static void ext4_sb_setlabel(struct ext4_super_block *es, const void *arg)
+{
+ /* Sanity check, this should never happen */
+ BUILD_BUG_ON(sizeof(es->s_volume_name) < EXT4_LABEL_MAX);
+
+ memcpy(es->s_volume_name, (char *)arg, EXT4_LABEL_MAX);
+}
+
+static
+int ext4_update_primary_sb(struct super_block *sb, handle_t *handle,
+ ext4_update_sb_callback func,
+ const void *arg)
+{
+ int err = 0;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct buffer_head *bh = sbi->s_sbh;
+ struct ext4_super_block *es = sbi->s_es;
+
+ trace_ext4_update_sb(sb, bh->b_blocknr, 1);
+
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, sb,
+ bh,
+ EXT4_JTR_NONE);
+ if (err)
+ goto out_err;
+
+ lock_buffer(bh);
+ func(es, arg);
+ ext4_superblock_csum_set(sb);
+ unlock_buffer(bh);
+
+ if (buffer_write_io_error(bh) || !buffer_uptodate(bh)) {
+ ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
+ "superblock detected");
+ clear_buffer_write_io_error(bh);
+ set_buffer_uptodate(bh);
+ }
+
+ err = ext4_handle_dirty_metadata(handle, NULL, bh);
+ if (err)
+ goto out_err;
+ err = sync_dirty_buffer(bh);
+out_err:
+ ext4_std_error(sb, err);
+ return err;
+}
+
+/*
+ * Update one backup superblock in the group 'grp' using the callback
+ * function 'func' and argument 'arg'. If the handle is NULL the
+ * modification is not journalled.
+ *
+ * Returns: 0 when no modification was done (no superblock in the group)
+ * 1 when the modification was successful
+ * <0 on error
+ */
+static int ext4_update_backup_sb(struct super_block *sb,
+ handle_t *handle, ext4_group_t grp,
+ ext4_update_sb_callback func, const void *arg)
+{
+ int err = 0;
+ ext4_fsblk_t sb_block;
+ struct buffer_head *bh;
+ unsigned long offset = 0;
+ struct ext4_super_block *es;
+
+ if (!ext4_bg_has_super(sb, grp))
+ return 0;
+
+ /*
+ * For the group 0 there is always 1k padding, so we have
+ * either adjust offset, or sb_block depending on blocksize
+ */
+ if (grp == 0) {
+ sb_block = 1 * EXT4_MIN_BLOCK_SIZE;
+ offset = do_div(sb_block, sb->s_blocksize);
+ } else {
+ sb_block = ext4_group_first_block_no(sb, grp);
+ offset = 0;
+ }
+
+ trace_ext4_update_sb(sb, sb_block, handle ? 1 : 0);
+
+ bh = ext4_sb_bread(sb, sb_block, 0);
+ if (IS_ERR(bh))
+ return PTR_ERR(bh);
+
+ if (handle) {
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, sb,
+ bh,
+ EXT4_JTR_NONE);
+ if (err)
+ goto out_bh;
+ }
+
+ es = (struct ext4_super_block *) (bh->b_data + offset);
+ lock_buffer(bh);
+ if (ext4_has_metadata_csum(sb) &&
+ es->s_checksum != ext4_superblock_csum(sb, es)) {
+ ext4_msg(sb, KERN_ERR, "Invalid checksum for backup "
+ "superblock %llu\n", sb_block);
+ unlock_buffer(bh);
+ err = -EFSBADCRC;
+ goto out_bh;
+ }
+ func(es, arg);
+ if (ext4_has_metadata_csum(sb))
+ es->s_checksum = ext4_superblock_csum(sb, es);
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+
+ if (err)
+ goto out_bh;
+
+ if (handle) {
+ err = ext4_handle_dirty_metadata(handle, NULL, bh);
+ if (err)
+ goto out_bh;
+ } else {
+ BUFFER_TRACE(bh, "marking dirty");
+ mark_buffer_dirty(bh);
+ }
+ err = sync_dirty_buffer(bh);
+
+out_bh:
+ brelse(bh);
+ ext4_std_error(sb, err);
+ return (err) ? err : 1;
+}
+
+/*
+ * Update primary and backup superblocks using the provided function
+ * func and argument arg.
+ *
+ * Only the primary superblock and at most two backup superblock
+ * modifications are journalled; the rest is modified without journal.
+ * This is safe because e2fsck will re-write them if there is a problem,
+ * and we're very unlikely to ever need more than two backups.
+ */
+static
+int ext4_update_superblocks_fn(struct super_block *sb,
+ ext4_update_sb_callback func,
+ const void *arg)
+{
+ handle_t *handle;
+ ext4_group_t ngroups;
+ unsigned int three = 1;
+ unsigned int five = 5;
+ unsigned int seven = 7;
+ int err = 0, ret, i;
+ ext4_group_t grp, primary_grp;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ /*
+ * We can't update superblocks while the online resize is running
+ */
+ if (test_and_set_bit_lock(EXT4_FLAGS_RESIZING,
+ &sbi->s_ext4_flags)) {
+ ext4_msg(sb, KERN_ERR, "Can't modify superblock while"
+ "performing online resize");
+ return -EBUSY;
+ }
+
+ /*
+ * We're only going to update primary superblock and two
+ * backup superblocks in this transaction.
+ */
+ handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 3);
+ if (IS_ERR(handle)) {
+ err = PTR_ERR(handle);
+ goto out;
+ }
+
+ /* Update primary superblock */
+ err = ext4_update_primary_sb(sb, handle, func, arg);
+ if (err) {
+ ext4_msg(sb, KERN_ERR, "Failed to update primary "
+ "superblock");
+ goto out_journal;
+ }
+
+ primary_grp = ext4_get_group_number(sb, sbi->s_sbh->b_blocknr);
+ ngroups = ext4_get_groups_count(sb);
+
+ /*
+ * Update backup superblocks. We have to start from group 0
+ * because it might not be where the primary superblock is
+ * if the fs is mounted with -o sb=<backup_sb_block>
+ */
+ i = 0;
+ grp = 0;
+ while (grp < ngroups) {
+ /* Skip primary superblock */
+ if (grp == primary_grp)
+ goto next_grp;
+
+ ret = ext4_update_backup_sb(sb, handle, grp, func, arg);
+ if (ret < 0) {
+ /* Ignore bad checksum; try to update next sb */
+ if (ret == -EFSBADCRC)
+ goto next_grp;
+ err = ret;
+ goto out_journal;
+ }
+
+ i += ret;
+ if (handle && i > 1) {
+ /*
+ * We're only journalling primary superblock and
+ * two backup superblocks; the rest is not
+ * journalled.
+ */
+ err = ext4_journal_stop(handle);
+ if (err)
+ goto out;
+ handle = NULL;
+ }
+next_grp:
+ grp = ext4_list_backups(sb, &three, &five, &seven);
+ }
+
+out_journal:
+ if (handle) {
+ ret = ext4_journal_stop(handle);
+ if (ret && !err)
+ err = ret;
+ }
+out:
+ clear_bit_unlock(EXT4_FLAGS_RESIZING, &sbi->s_ext4_flags);
+ smp_mb__after_atomic();
+ return err ? err : 0;
+}
+
/**
* Swap memory between @a and @b for @len bytes.
*
@@ -847,6 +1089,64 @@ static int ext4_ioctl_checkpoint(struct file *filp, unsigned long arg)
return err;
}
+static int ext4_ioctl_setlabel(struct file *filp, const char __user *user_label)
+{
+ size_t len;
+ int ret = 0;
+ char new_label[EXT4_LABEL_MAX + 1];
+ struct super_block *sb = file_inode(filp)->i_sb;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ /*
+ * Copy the maximum length allowed for ext4 label with one more to
+ * find the required terminating null byte in order to test the
+ * label length. The on disk label doesn't need to be null terminated.
+ */
+ if (copy_from_user(new_label, user_label, EXT4_LABEL_MAX + 1))
+ return -EFAULT;
+
+ len = strnlen(new_label, EXT4_LABEL_MAX + 1);
+ if (len > EXT4_LABEL_MAX)
+ return -EINVAL;
+
+ /*
+ * Clear the buffer after the new label
+ */
+ memset(new_label + len, 0, EXT4_LABEL_MAX - len);
+
+ ret = mnt_want_write_file(filp);
+ if (ret)
+ return ret;
+
+ ret = ext4_update_superblocks_fn(sb, ext4_sb_setlabel, new_label);
+
+ mnt_drop_write_file(filp);
+ return ret;
+}
+
+static int ext4_ioctl_getlabel(struct ext4_sb_info *sbi, char __user *user_label)
+{
+ char label[EXT4_LABEL_MAX + 1];
+
+ /*
+ * EXT4_LABEL_MAX must always be smaller than FSLABEL_MAX because
+ * FSLABEL_MAX must include terminating null byte, while s_volume_name
+ * does not have to.
+ */
+ BUILD_BUG_ON(EXT4_LABEL_MAX >= FSLABEL_MAX);
+
+ memset(label, 0, sizeof(label));
+ lock_buffer(sbi->s_sbh);
+ strncpy(label, sbi->s_es->s_volume_name, EXT4_LABEL_MAX);
+ unlock_buffer(sbi->s_sbh);
+
+ if (copy_to_user(user_label, label, sizeof(label)))
+ return -EFAULT;
+ return 0;
+}
+
static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct inode *inode = file_inode(filp);
@@ -1261,6 +1561,13 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT4_IOC_CHECKPOINT:
return ext4_ioctl_checkpoint(filp, arg);
+ case FS_IOC_GETFSLABEL:
+ return ext4_ioctl_getlabel(EXT4_SB(sb), (void __user *)arg);
+
+ case FS_IOC_SETFSLABEL:
+ return ext4_ioctl_setlabel(filp,
+ (const void __user *)arg);
+
default:
return -ENOTTY;
}
@@ -1336,6 +1643,8 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case EXT4_IOC_GETSTATE:
case EXT4_IOC_GET_ES_CACHE:
case EXT4_IOC_CHECKPOINT:
+ case FS_IOC_GETFSLABEL:
+ case FS_IOC_SETFSLABEL:
break;
default:
return -ENOIOCTLCMD;
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index b63cb88ccdaede8e6fa8629a2fe544a2920c0c60..ee8f02f406cb6ca9d6601a72a6f143d146ade97c 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -717,12 +717,23 @@ static int setup_new_flex_group_blocks(struct super_block *sb,
* sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
* For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
*/
-static unsigned ext4_list_backups(struct super_block *sb, unsigned *three,
- unsigned *five, unsigned *seven)
+unsigned int ext4_list_backups(struct super_block *sb, unsigned int *three,
+ unsigned int *five, unsigned int *seven)
{
- unsigned *min = three;
+ struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+ unsigned int *min = three;
int mult = 3;
- unsigned ret;
+ unsigned int ret;
+
+ if (ext4_has_feature_sparse_super2(sb)) {
+ do {
+ if (*min > 2)
+ return UINT_MAX;
+ ret = le32_to_cpu(es->s_backup_bgs[*min - 1]);
+ *min += 1;
+ } while (!ret);
+ return ret;
+ }
if (!ext4_has_feature_sparse_super(sb)) {
ret = *min;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 435f24787030ad7b6f797f269f5d328294d99a72..806ce08933226d2e14c606c93103dab97ad93e60 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -279,8 +279,8 @@ static int ext4_verify_csum_type(struct super_block *sb,
return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
}
-static __le32 ext4_superblock_csum(struct super_block *sb,
- struct ext4_super_block *es)
+__le32 ext4_superblock_csum(struct super_block *sb,
+ struct ext4_super_block *es)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
int offset = offsetof(struct ext4_super_block, s_checksum);
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index 0ea36b2b0662a333bf1ca9d348393c0ce97803e4..19e957b7f94100785f93b99aeec4e5f7368b0b70 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -2837,6 +2837,29 @@ TRACE_EVENT(ext4_fc_track_range,
__entry->end)
);
+TRACE_EVENT(ext4_update_sb,
+ TP_PROTO(struct super_block *sb, ext4_fsblk_t fsblk,
+ unsigned int flags),
+
+ TP_ARGS(sb, fsblk, flags),
+
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(ext4_fsblk_t, fsblk)
+ __field(unsigned int, flags)
+ ),
+
+ TP_fast_assign(
+ __entry->dev = sb->s_dev;
+ __entry->fsblk = fsblk;
+ __entry->flags = flags;
+ ),
+
+ TP_printk("dev %d,%d fsblk %llu flags %u",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->fsblk, __entry->flags)
+);
+
#endif /* _TRACE_EXT4_H */
/* This part must be outside protection */